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951.
952.
Artur Hideyuki Tomita 《Proceedings of the American Mathematical Society》2003,131(8):2617-2622
E. K. van Douwen asked in 1980 whether the cardinality of a countably compact group must have uncountable cofinality in . He had shown that this was true under GCH. We answer his question in the negative. V. I. Malykhin and L. B. Shapiro showed in 1985 that under GCH the weight of a pseudocompact group without non-trivial convergent sequences cannot have countable cofinality and showed that there is a forcing model in which there exists a pseudocompact group without non-trivial convergent sequences whose weight is . We show that it is consistent that there exists a countably compact group without non-trivial convergent sequences whose weight is .
953.
Nanosecond pulses of a Nd:YAG laser have been employed to deposit thin-film zinc telluride (ZnTe) on silicon (Si) and glass without heating these substrates. We present and discuss the structural and surface properties of films deposited at 1064 nm and 532 nm. X-ray diffraction and analysis of the surface roughness with atomic force microscopy reveal that the material texture and surface morphology depend on the ablation laser line used rather than on the substrate. The observations contribute to improved understanding of pulsed-laser deposition and provide tools to optimize the optoelectronic and photonic properties of ZnTe thin-films as well as their incorporation into Si-based technologies in order to fabricate cost-effective and functional optoelectronic devices and all-optical laser digitizer. 相似文献
954.
Artur Nicolau 《Journal d'Analyse Mathématique》1994,62(1):199-224
We study when a Pick-Nevanlinna problem with more than one solution can be solved by an interpolating Blaschke product.
Supported in part by the grant PB85-0374 of the CYCIT, Ministerio de Educación y Ciencia, Spain. 相似文献
955.
LetH
∞ be the algebra of bounded analytic functions in the unit diskD. LetI=I(f
1,...,f
N) be the ideal generated byf
1,...,f
N∈H
∞ andJ=J(f
1,...,f
N) the ideal of the functionsf∈H
∞ for which there exists a constantC=C(f) such that |f(z)|≤C(|f
1
(z)|+...;+|f
N
(z)|),z∈D. It is clear that
, but an example due to J. Bourgain shows thatJ is not, in general, in the norm closure ofI. Our first result asserts thatJ is included in the norm closure ofI ifI contains a Carleson-Newman Blaschke product, or equivalently, if there existss>0 such that
Our second result says that there is no analogue of Bourgain's example in any Hardy spaceH
p, 1≤p<∞. More concretely, ifg∈H
p and the nontangential maximal function of
belongs toL
p (T), theng is in theH
p-closure of the idealI.
Both authors are supported in part by DGICYT grant PB98-0872 and CIRIT grant 1998SRG00052. 相似文献
956.
Artur P. Terzyk Magdalena S. ?wiertnia Marek Wi?niewski Piotr A. Gauden Gerhard Rychlicki Grzegorz S. Szymański 《Applied Surface Science》2007,253(8):4006-4009
We present the results of benzene adsorption at the acidic pH level determined on the series of chemically modified activated carbons and at three temperatures. The influence of carbon surface chemical composition on benzene adsorption is discussed. It is shown that the decrease in the pH level from 7 up to 1.5 increases benzene adsorption and the only exception is carbon modified with gaseous ammonia. Basing on the results of current work and those published previously (for phenol, paracetamol, acetanilide and aniline) and using the results of quantum chemistry calculations (DFT, Gaussian 98) we show, that the value of the energy of interaction with unit positive charge is crucial during the analysis of the influence of pH level on adsorption. Obtained results allow to predict the changes in adsorption of aromatics on carbons with the decrease in the pH level. 相似文献
957.
Artur Guchowski Ewa Czarniecka-Skubina Jarosawa Rutkowska 《Molecules (Basel, Switzerland)》2020,25(23)
This study was performed in order to assess technological characteristics, proximate composition, fatty acids profile, and microbiological safety of sous-vide processed salmon in comparison with steaming and roasting. The cooking loss was lower in the sous-vide method (6.3–9.1%) than in conventional methods (11.6–16.2%). The preparation of salmon using sous-vide was more time- and energy-consuming than steaming. The dry matter content of the salmon fillets was higher in conventionally processed samples than sous-vide due to the evaporation of water, and it was connected with total protein (r = 0.85) and lipid content (r = 0.73). Analysis of the fatty acids profile only revealed significant differences in six fatty acids. All of the heat treatment methods ensured microbiological safety with regard to coagulase-positive Staphylococcus, E. coli, Listeria monocytogenes, and Salmonella spp. However, in sous-vide (57 °C, 20 min) and steamed samples after storage Enterobacteriaceae bacteria (<104) was detected. Summing up, high parameters of sous-vide salmon cooking, when considering both technological parameters, nutritional value, and microbiological status should be recommended. 相似文献
958.
ukasz opusiewicz Emilia Drozowska Paulina Trocer Pawe Kwiatkowski Artur Bartkowiak Annett Gefrom Monika Sienkiewicz 《Molecules (Basel, Switzerland)》2020,25(24)
Plant derived fermented beverages have recently gained consumers’ interest, particularly due to their intrinsic functional properties and presence of beneficial microorganisms. Three variants containing 5%, 10%, and 15% (w/w) of sweet blue lupin (Lupinus angustifolius L. cv. “Boregine”) seeds were inoculated with kefir grains and incubated at 25 °C for 24 h. After processing, beverages were stored in refrigerated conditions (6 °C) for 21 days. Changes in microbial population, pH, bioactive compounds (polyphenolics, flavonoids, ascorbic acid), reducing sugars, and free amino acids were estimated. Additionally, viscosity, firmness, color, and free radicals scavenging properties were determined. Results showed that lactic acid bacteria as well as yeast were capable of growing well in the lupin matrix without any supplementation. During the process of refrigeration, the viability of the microorganisms was over the recommended minimum level for kefir products. Hydrolysis of polysaccharides as well as increase of free amino acids was observed. As a result of fermentation, the beverages showed excellent DPPH, ABTS+·, ·OH, and O2− radicals scavenging activities with a potential when considering diseases associated with oxidative stress. This beverages could be used as a new, non-dairy vehicle for beneficial microflora consumption, especially by vegans and lactose-intolerant consumers. 相似文献
959.
Jacob J. Lacharity Artur K. Mailyan Karen Y. Chen Armen Zakarian 《Angewandte Chemie (International ed. in English)》2020,59(28):11364-11368
An asymmetric total synthesis of [13C4]‐anatoxin‐a ([13C4]‐ 1 ) has been developed from commercially available ethyl [13C4]‐acetoacetate ([13C4]‐ 15 ). The unique requirements associated with isotope incorporation inspired a new, robust, and highly scalable route, providing access to 0.110 g of this internal standard for use in the detection and precise quantification of anatoxin‐a in freshwater. A highlight of the synthesis is a method that leverages a cyclic iminium ion racemization to achieve dynamic kinetic resolution in an enantioselective Morita–Baylis–Hillman (MBH) cyclization. 相似文献
960.
Ricardo M. Campos Alexandre C. P. M. Alves Marco A. L. Lima Artur F. M. Farinha João P. S. Cardoso Prof. Adélio Mendes Dr. José C. S. Costa Prof. Luís M. N. B. F. Santos 《Chemphyschem》2020,21(16):1814-1825
In this study, a homogeneous thin film growth of pentacene onto indium tin oxide (ITO) coated glass surfaces is explored using a high-resolution and reproducible vapor deposition methodology. Moreover, vacuum thermal evaporation of ionic liquids (ILs) ([C2C1im][NTf2] and [C2C1im][OTF]) onto ITO, gold/palladium (AuPd) and pentacene surfaces were performed. A greater wettability behavior of ILs is observed for surfaces containing AuPd. Sequential and simultaneous depositions of ILs and pentacene were explored. Simultaneous depositions lead to the formation of nanocomposites films, consisting of IL micro- and nanodroplets covered by pentacene layers. Plasma surface treatment was used to induce the ILs droplets coalescence and explore the dynamics and phase separation of the nanocomposites. The [C2C1im][OTF] droplets were found to be completely covered with pentacene, which suggests a great affinity between cation-anion pairs and the aromatic moiety. Pentacene films and their nanocomposites with ILs exhibit a typical optical band gap of Egap=1.77 eV, indicating that the nanocomposite phase domains are large enough to behavior as the bulk. 相似文献